It is known to deploy an inflatable vehicle occupant protection device, such as an air bag, upon the occurrence of an event for which occupant protection is desired, such as a vehicle collision or rollover. The air bag is part of a conventional vehicle occupant protection apparatus that includes a sensor and an inflation fluid source, such as an inflator. Upon sensing the occurrence of an event for which deployment of the air bag is desired, the inflation fluid source is actuated and produces inflation fluid that inflates the air bag, causing it to deploy into the vehicle occupant compartment to help protect the vehicle occupants.
One particular type of inflatable vehicle occupant protection device is a passenger frontal air bag. Passenger frontal air bags are typically stored in a deflated condition in a housing that is mounted behind a class A surface of the vehicle instrument panel. A cover, which can form a portion of the class A surface, is connectable with the housing and/or instrument panel to help enclose and conceal the air bag in a stored condition. Upon deployment of the passenger air bag, the forces exerted on the cover by the inflating air bag cause the cover to rupture or otherwise open, which permits the air bag to inflate and move to a deployed position.
Another type of inflatable vehicle occupant protection device is an inflatable knee air bag. Knee airbags are typically stored in a housing or canister that is mounted in the area of the lower portion of the instrument panel and the vehicle foot well. Knee air bags are inflatable to a deployed condition in which the air bag is positioned between the occupant's legs and the instrument panel to help protect the vehicle occupant.